Google is celebrating the discovery of the Sơn Đoòng Cave cave in its new Google Doodle.
The once-forgotten cave was rediscovered in 2009 and contains amazing natural wonders and even a community of monkeys contained within its staggering, jagged walls of limestone rock.
Google often marks an incredible discovery, the achievements of significant people or the world's natural wonders with a special Google Doodle on appropriate days.